Drying apparatus for photographsc



Jan. 31, 1956 J. s. GARFINKLE 2,732,629

DRYING APPARATUS FOR PHOTOGRAPHIC PRINTS Filed Dec. 10, 1952 3 Sheets-Sheet l Jan. 31, 1956 J. s. GARFINKLE DRYING APPARATUS FOR PHOTOGRAPHIC PRINTS Filed Dec. 10, 1952 3 Sheets-Sheet 2 .Fi 4 n 2 Jan. 31,1956

J. s. GARFINKLE 2,732,629 DRYING'APPARATUS FOR PHOTOGRAPHIC PRINTS Filed Dec. 10, 1952 3 Sheets-Sheet 3 by mm. rmm

United States Patent ce 2,732,62? DRYING; APPARATUS FORBHQTOGRAPHIC PRINTS Joseph S. Garfinkle, Boston, Mass. Application December 10, 1952, Serial No. 325,201 1 Claim. (Cl. 34-123) This invention relates to apparatus for drying photographic prints.

The quality and type of finish of a photographic print depends to a considerable extent on the manner of drying the print after it is developed. For example, if a glossy finish is desired, the print is pressed on a hard, polished surface while drying. Softer finishes are produced by pressing the print on a dull surface. In any case, it is necessary that the pressure be uniform and that formation of air bubbles, which result in spots and imperfections, be avoided. Furthermore, air drying at room temperature is too slow for many commercial purposes, and artificial heat is sometimes employed to shorten the drying time. In that case, the drying time and temperature must be carefully controlled, as too long exposure is likely to cause cracking and curling. Most of the artificially heated drying devices now in use are too cumbersome and expensive to be practicable for the amateur photographer or the small photographic shop.

The object of this invention is to provide a drying apparatus, by means of which prints may be rapidly dried by artificial heat, in which the drying time may be easily controlled by the operator, which insures uniform pressure all over the print, which eliminates air bubbles, which is readily adaptable for producing various finishes, and which is sufficiently inexpensive in construction and simple in operation to be practical for amateur as well as professional photographers.

Fig. 1 is front elevation, partially broken away, of a drier constructed according to the invention.

Fig. 2 is a cross section of the main shaft mounting taken along line 22 of Fig. 1.

Fig. 3 is an end view of the drier.

Fig. 4 is a cross-section of the drive roll mounting taken along line 4-4 of Fig. 1, and

Fig. 5 is a cross-section taken along line 5-5 of Fig. 1.

The drier is supported on a rigid frame work consisting of trapezoidal end panels 7 and 8 having bent in edges, connected at the bottom by front and rear angles 9 and 10, and at the top by a channel 11. A stationary tubular shaft 12, having threaded ends, is mounted on the end panels and secured by nuts 13 and 14. Mounted to rotate about this shaft is a hollow metal drum 15, of sufficiently heavy gauge to insure uniform heat distribution.

The mounting of the drum is illustrated in Fig. 2. A threaded bushing 17 having an external flange 18 is mounted on the right hand end wall 16 of the drum and secured against the wall by a nut 19. The bushing is rotatable about a shaft 12. A spacing collar 20 on the shaft prevents axial movement of the drum. The mounting at the left hand side of the drum is similar. For convenience in assembly the drum may be split centrally or may have a detachable end wall. The drum has end rims 23 and 24 between which is mounted a detachable jacket 25. The jacket may be made in the form of two semi-cylindrical shells for convenience and is held in place by any suitable fastening such as screws. A strip of adhesive fabric 26 may be applied to cover the joint along the front to pro- 2,732,629 Patented Jan; 31, T956 vide a continuous, relatively water proof' surface. For the glo'ssier' print surfaces, a jacket witha suitable outside surface. would be used, fo'r'example, thev jacket may be chrome-plated, or enamelle'd, or maybe made of a metal kn'o'wninthe trade-asFerrotype;'Fordhlltypes of'finish; thejacket may be readily replaced by a' jacket with a duller enameled surface. For an extremely dull finish, the print may be matt dried by reversing it so that the printed side is in contact with the belt.

Mounted on shaft 12 inside the drum is an electrical heating element 21 which is wound on an insulating core 22. The leads 27 for the heating element, are brought in through an opening 28 in the shaft.

Mounted on the upper part of the frame is a shaft 30, one end of which projects through an elongated opening in panel 7. A hand knob 31 is connected to the projecting end of shaft 30. A roller 32, of hard rubber or similar material is mounted on shaft 30. The mounting of one end of the shaft 30 is illustrated in detail in Fig. 4. A slide 33 is attached to panel 8 parallel to the bent over front edge 34 of the panel. Shaft 30 is journalled in a block 35 slidably mounted between slide 33 and edge 34. The end of the shaft projects through an elongated opening 41 in the panel. A screw eye 36 is attached to the block. A second screw eye 37, the lower end of which is shown in Fig. 5, projects through a bracket 38 attached to the lower part of panel 8, and is adjustably secured by means of a wing nut 39. Connected between the two screw eyes is a tension spring 40. As shown in Fig. 1, the right hand end of shaft 30 is similarly journalled in a block 42 slidable between a slide 43 and bent over front edge 44 of panel 7. Block 42 is connected by means of a screw eye 45 to one end of a tension spring 46, the other end of the spring being adjustably secured by means of a screw eye 47 retained in bracket 48 by means of wing nut 49. By means of this arrangement, the roller 32 is spring pressed against the drum 15, and the spring tension may be readily adjusted to secure the desired pressure.

Journalled on end plates 7 and 8 are three other shafts 50, 51 and 52, one at the top, and two at the bottom in front and back of the drum. An endless belt 53 traverses roller 32 and runs over the outside of shafts 50, 51 and 52 and back over the surface of drum 15. Roller 32 serves as a friction drive for both the belt and the drum. By turning the hand knob 31 counterclockwise, as viewed in Fig. 3, drum 15 is caused to revolve clockwise, and at the same time belt 53 is driven in such a manner as to follow the drum. By turning the knob in the opposite direction the motion of the drum and belt is reversed.

To operate the device, the electric heating element is first energized through a switch or other conventional means. When the drum has become suificiently heated, the upper edge of a print'is inserted under roller 32 between the belt and the drum, and hand knob 31 revolved so as to carry the print over the back of the drum. The pressure of roll 32, as the print advances under it, squeezes out any air bubbles, and the belt holds the print firmly against the drum surface. To remove the print, the rotation of knob 31 is reversed bringing the drum back to its original position. To shorten or lengthen the drying period, the operator may turn the knob faster or slower in either direction. If the emerging edge of the print does not appear completely dry, the operator can return the print to the drying position for a few seconds longer. It has been found that an operator can readily judge, after one or two trials, the proper speed for turning the knob so as to dry the print by a single half turn of the drum in each direction.

What is claimed is:

A drier for photographic prints comprising a supporting frame, a stationary shaft mounted on said frame, a drum rotatably mounted on said shaft, a heating element mounted within said drum, a pair of blocks mounted on said frame and slidable in a plane parallel to said shaft, a drive roll rotatably mounted on said blocks parallel to said axis, a hand knob attached to said drive roll for imparting rotation thereto, a pair of springs attached to said blocks and adapted to urge said blocks toward said drum, a plurality of rollers disposed parallel to said shaft adjacent to said drum, and a belt passing around said drive roll and said rollers, said rollers being arranged to hold a portion of said belt in contact with said drum, and said 10 drive roll being so disposed drum simultaneously by frictional engagement.

References Cited in the file of this patent UNITED STATES PATENTS as to drive said belt and said 

